help with 1) manual gears oils ect 2) Clutch problems

Hi ATS need some advice

( 4 cylinder engine, manual gearbox )

1 Is transmission oil/fluid the same as gear box oil?

My mechanic suggested it may be dearer than engine oil but he would price when I bought the car in

According to log book it needs replacing @ 200,000 kms

2. He tentatively agreed that it shouldnt take longer than 1 hrs labour plus cost of trans fluid

3. My logic thinks that Trans oil should be cheaper than engine oil, as the pistons are running harder and longer than your gear changes.

Please offer advice. I googled but couldnt find the exact answers without going into in-depth research ( I'm time poor at the moment and thought the great minds here would help )

This what my next main concern is....

4. I had a problem with my brake fluid a few weeks ago. They topped it up and hand brake light indicator reset to normal.

now 2 days ago......

5. The gear box made a weezing sound every time I shifted gears.

6. A mech did a quick fix by bleeding the air and pumping the clutch pedal. He noticed fluid leaking on the firewall under the brake and clutch pedals. He meant well, fixed it, and said "fix it sooner than later!!!" .
Sure enough I continued my courier deliveries, but 15 minutes later the pedal "came loose" and I was stuck in traffic and unable to change gears. Towed the car and due to go in on Monday for a fix.

Would the gearbox be damaged, or the clutch, or is it a simple fix of cables on the clutch?

I'd just like input as to what sort of labour time/hrs I'd be looking at. They're pretty good mechs and are busy with other high profit tyre supply/fitting so they dont overcharge on their jobs with me.

I'll need to make an informed quick decision on Monday as time spent off road means no income.

All helpful sound advice would be appreciated.

Kill it with fire.

Claim the insurance.

J/K. Don't do that. Insurance fraud is bad, bad, bad!


ETA: Make/model of the vehicle, would certainly aid troubleshooting efforts. Just saying...

a reply to: TheConstruKctionofLight

You should probably start with a year/make/model.

Some manual transmissions use special oils.

Secondly...

Manual clutches generally use brake fluid for their hydraulics.

However, you having a parking or brake light on means that your brake master cylinder was low on fluid.

I'm not aware of any vehicle that shares the brake master cylinder fluid with the clutch master cylinder.

But I don't know everything.

If you have fluid leaking out into the firewall inside of the vehicle and he pumped the clutch to bleed it you have probably blown a seal in your clutch master cylinder.

Can't really advise you on anything else without a year/make/model.

Except if it is leaking fluid onto your floorboard it would be wise not to drive it until it is fixed.

It's probably a hydraulic clutch. The transmission oil is usually vehicle specific, I would change it at about a hundred twenty thousand miles or so, it does break down and collects condensation around here. I look more at years to judge that, it takes probably fifteen years or so for us to put that many miles on one of our cars.

I'm an expert at this....

Crap can the whole thing, it must be shot to crap if the gearbox makes any noise,.....and get a Toyota......

originally posted by: madmac5150
Kill it with fire.

Claim the insurance.

J/K. Don't do that. Insurance fraud is bad, bad, bad!


ETA: Make/model of the vehicle, would certainly aid troubleshooting efforts. Just saying...

Transmission fluid/gear box fluid is almost always more expensive and it is very different than engine oil. Engine oil is changed every ~5000Km or so, Transmission every 200,000K, so that alone should tell you it will be more expensive - it has to last a lot longer.

IDK what is in transmission oil but it burns much hotter, smokes more and has about 20% more BTU per gallon, which alone tells you it's something very different.

To Lumeri, Ricky and DigginFoTroof,

4 in-line Cylinder 2008, manual 5 speed, 2.4 litre,

Most appreciated and answers some of my thoughts.


@ 4.33 where his toe is - is where I've got some fluid leaking



Lumenari, this was most helpful

Manual clutches generally use brake fluid for their hydraulics.

However, you having a parking or brake light on means that your brake master cylinder was low on fluid.

I guess I will wait and see what the full diagnosis is on Monday

a reply to: GBP/JPY

I can appreciate that, at the time the Toyota was 30% more expensive and gained no advantage other than Auto trans and slightly larger cargo bay. Knowing from other couriers how expensive the Toyota was to service I think I made a better choice over the life of the vehicle.

a reply to: TheConstruKctionofLight

1 : totally different oils with great differance in viscosity and operating temperatures.

2: gearbox oil change is a 15 min job so minimum 1hr plus CORRECT oil is aok.

3: transmission oil dearer than eng oil as working harder in smaller compact space with much higher operating temperature.

4 & 5 : brake master cylinder piston sleeve rubber leaking allowing air in so bleeding will fix only for so long till enough fluid bypasses the rubber again allowing furher loss of braking traction.
Weezing in box when shifting is totally unrelated to brakes themselve. Will likely be clutch master cylinder (small reservoir on firewall) suffering same issue as described above for brake master cylinder or leaking into bellhousing causing clutch itself to slip ever so slightly due to having fluid on it.

a reply to: TheConstruKctionofLight

Could be clutch master cylinder leaking. I think there are repair kits that are pretty cheap (a bunch of seals).

Totally depends what car.

a reply to: TheConstruKctionofLight

If it's a hydraulic clutch, which it probably is, it will need to be bled to remove the air. I had my clutch replaced last year and had much the same problem. My truck has a total system replacement requirement, everything from under the hood right down to the clutch needs to be replaced as an entire assembly. It's not made any more. So the mechanic has to do a tricky maneuver the end of the line has to be held in a certain position to release the air. Until that was done, I was almost dead in the water, unable to shift gears.

It took me a week to find the clutch bleeding trick for my truck - once he saw the instructions, my mechanic had it done in a half hour.

This is probably what is happening to you, the clutch isn't releasing. The dripping under the hood is probably due to the air in the line, pushing fluid out all over the place. That's what happened to me at any rate.

And your gearbox lube may very well be specific to your transmission. The oil for mine costs $90 per quart, 2 quarts required. Do NOT attempt to save some money by shoving the wrong kind of oil in there because a new transmission is far more expensive than the oil.

If you do not have the service book where this is noted.. The best way to find out is get the cars papers and lookup the exact make. Then you can get the service book and type of fluids.

But this should be your mechanics job.

a reply to: DigginFoTroof
5000km oil changes are unnecessary unless you are running in the higher load curve... I get done a full oil change on the RB28/30 after around 3000-5000 km and my daily needs one every 15000km.

But you are right with the difference in the oils. The transmission oil is designed to be more fluid so the internal drag on the gears is reduced.

a reply to: CthruU

& billxam

Thanks to both of you for the detailed reply. I'm starting to get a clearer picture & it'll all depend on the inspection on Monday.

Gear oil is GL-5 made for diffs and contains friction modifier additives.

GL-4 spec MTF manual trans fluid is for transmissions and contains no or less friction modifiers so the synchronizers can grab each other.

Many older trans took 10w-30 motor oil, but you can't use "API Starburst" energy-efficient motor oil for the same reasons, so....

Pennzoil made a specialized replacement called "Synchromesh", GM brands their own. At 10cSt it's much thinner than 75w-90 gear oil at 15cSt, replacing any and all MTFs. Some oems use incredibly thin MTF, thinner than ATF around 6cSt, so going "up" to Synchromesh OR "down" from a 90 weight to Synchromesh, is no problem, it's well advised and standard practice for the last 10 years....new to old shop mechanics. Google it. Remember, old school gear oil sheers to a great extent, so using a modern product that won't sheer, but starts out thinner is the same exact thing (when talking with old mechanics).

Bottom line is PZ Synchromesh is awesome. State-of-the-art formulation replacing everything except GL-5 75w-90 GEAR OIL. It's all about the friction modifiers and your synchros, the viscosity can be lowered or raised depending on engine tune, and mostly climate. GREAT in cold. In extreme cold, people used ATF in their MT so they could shift. Again here, you don't use the friction modified ATFs, like ATF+4 or Universal....use Merc V or pref Dexron 6.

Anyway, PZ Synchromesh, it's awesome and dirt cheap. Redline has some MTFs too, from a thin 10cSt 75w-80, to a midweight 12cSt "85" so you don't have to mix your own, to MT 90. Some decent white papers on their site too.

"The gear box made a wheezing sound every time I shifted gears."

If that wheezing sound occurs when you depress the clutch pedal and hold it down, it's a worn throw-out bearing. This is a large thrust bearing in the engine's bell housing, between the hydraulically-actuated throw-out fork and the clutch's spring loaded pressure plate. This bearing does wear, and needs replacement. Generally it is replaced when the clutch is serviced. It's not an expensive part.

a reply to: TheTruthRocks

thanks, the day before this started to play up a mech did diagnose the "cheap throwaway part" was likely the culprit just by the wheezing sound.